This invention relates generally to the art of machine tools and more particularly to a workholder for use in a computer numerically controlled apparatus.
Metallic shafts have for a great many years had key ways cut therein so as to facilitate the use of those shafts to transmit rotational forces from one apparatus to another. Traditionally, such apparatus has been utilized for the coupling of an engine to a transmission or a transmission to an apparatus where rotation is required. The machining of these key ways has traditionally been carried out on a horizontal lave under the supervision of a machinist who assures that the key way is cut with precise dimensions. Typically, a machinist will supervise the operation of one or two laves at a time.
In relatively recent history, computer numerically controlled apparatus have come about to replace a machinist for a number of machining operations. These apparatuses include a plurality of working tools and have the ability to change working tools and complete machining operations with the worker having to only load and unload the apparatus. Due to the high speed and precision of the milling machines utilized within a computer numerically controlled apparatus, such apparatuses have been housed in rather complex enclosures so as to contain all metal fragments and lubricating oil provided during the machining operation. Such apparatuses normally have a closure so as to permit placement and removal of a workpiece into the computer numerically controlled apparatus. Due to the expense of computer numerically controlled apparatuses and the complexity of loading and unloading the apparatuses, such apparatuses have normally only been utilized for very complex machining operations.
A number of prior art patents have been directed to milling machines and workholders which are listed here for background information. These patents include U.S. Pat. No. 3,926,421 to Reiger, Jr. et al.; U.S. Pat. No. 4,414,732 to Tomita, et al.; U.S. Pat. No. 4,091,526 to Nakaso, et al.; U.S. Pat. No. 4,185,377 to Nakaso, et al.; U.S. Pat. No. 4,356,621 to Tomita, et al.; U.S. Pat. No. 4,574,441 to Kronfeld; U.S. Pat. No. 4,436,462 to Martinez; U.S. Pat. No. 3,724,964 to Needham, Jr.; U.S. Pat. No. 2,342,829 to Armitage; U.S. Pat. No. 2,387,820 to Armitage, et al.
While a variety of apparatuses exist for milling and machining, there exists a need-to further increase the efficiency of machining operations particularly as related to the use of computer numerically controlled apparatuses.